Improvement in devices for supporting and connecting school-desks



UNITED STATES JAMES S. BANKIN, OF MINNEAPOLIS, MINNESOTA.

IMPROVEMENT IN DEVICES FR SUPPORTING AND IIIJNNEIITINIi SCHOOL-DESKS.

Specification forming part of Letters Patent No. 121,471, dated December5, 1871.

A in convenient sections or lengths, which fit and are secured together,and in the peculiar manner of joining the parts, for the purposehereinafter described.

In the drawing, Figure l is a side elevation of three school-desksconnected in my improved manner; Fig. 2, a horizontal vertical sectionof the same; Fig. 3, a perspective view of a sec- 'tion of the beamdetached; Fig. 4, a vertical crosssection in plane of line x w, Fig. 1,Fig. 5, a perspective view of several sections provided with dovetailsand mortises; Fig. 6, a cross-section of two lengths as connected bydovetail and mortises. n

A A A represent school-desks of ordinary construction, which areconnected and supported in an upright position by a central horizontalbeam,

B. The latter is made in sections, preferably of the form shown at B' B'B', which are respectively secured to separate desks between the seat aand under side of the desk-shelf a' in any suitable manner. Thesesections B B intermatch and are connected to each other to form acontinuous beam.

I prefer to form and connect the different lengths in the followingmanner, although any other plan may be adopted that may be foundconvenient: An upper length, b, of the section B', Fig. 2, is formedwith a projecting tongue or tenon, b1, which fits into a correspondinggroove,

c1, cut in the upper edge of the length c. These two lengths b c overlapand are secured to each other a portion of their length, leaving ends b2c2 projecting outward in opposite directions.

In use, one whole section, B', is attached to each desk by securing theupper length b to the under side of the desk-shelf a', and the lowerlength c to the up per side of the seat a. To connect and support thedesks, the projecting ends b2 of the upper lengths b are lapped over andmatched with the ends c2 of the lower lengths c, and firmly securedtogether by means of screws or other convenient methods, the tongue b1and groove c1 insuring a close and reliable unity of parts. If desired,the different lengths b c need not be secured to each other, asdescribed, until during the operation of setting up the desks, thuseconomizing space in transportation.

In some cases, to avoid the employment of screws and similar fastenings,and to render the parts more convenient to transport, put together,Sto., I intend to provide the different lengths with vertical andhorizontal dovetails and niortises m m n u, Figs. 5 and 6, and, inputting together, the horizontal connections are so arranged as to breakjoints with and lock the vertical connections. The beam lmay also beattached to the desk and seat in a similar manner, the numerous jointsall combining to sustain and lock each other.

Among the many advantages secured by my constructionmay be mentioneditspeculiar adaptation for packing and transportation, and the ease andrapidity with which the parts may be put together, forming a perfectlysecure and reliable beam, possessing to all intents and purposes theadvantages of an integral beam with none of its defects. By the use ofshort sections, as described, great economy is attained in both materialand manufacture. Short lengths of lumber can be more easily procured,and there is less waste than when long lengths are employed. The shortlengths can also be more quickly and conveniently handled, and admit ofthe substitution of machine for hand-work, heretofore employed. Anothergreat advantage secured by my plan is that the danger from warping isreduced to a minimum, the long beams, when formed in one piece, as ofold, frequently being rendered useless from this cause. As a result ofthe numerous advantages secured by my improved construction the cost ofthe whole is greatly reduced.

In the patent granted to me February 18, 1862, I claim a continuouswooden beam.

What I now claim as my invention, and desire to secure by Letters`Batent, is-

The central beam B, formed of a series of sections by the combination ofthe upper lengths b and the under lengths c, constructed, substantiallyas described, for supporting and connecting a series of school-desks, asset forth.

In witness whereof I have hereunto signed my name in the presence of twosubscribing witnesses.

Witnesses: JAMES S. RANKIN.

GEO. W. MIATT, J. B. GEEHENHAGEN. (62)

